Moog Model 905 Rotary Servo Actuator

The Moog Model 905 Rotary Servo Actuator is a DC rotary servo actuator for positioning the flight control surfaces of uncrewed aircraft. It is used on the AQM-37D target drone and is designed to operate under extreme environmental conditions. Variants of the actuator can be tailored to a specific application through the maker's applications engineers.

The rotation range is a stroke of ±33°, which sets the deflection available at the control surface, and the no-load speed is 250 °/s, which indicates the slew rate when the surface carries no aerodynamic load. The datasheet also defines a rated torque, a peak torque and a power point at a reduced speed, so integrators should size hinge loads against the rated figures and reserve the peak value for transient demands. Mass is 1,360.78 g, which feeds directly into the weight and balance budget of the airframe.

Inside, a SmCo permanent magnet DC motor drives high efficiency steel gearing with low backlash, which supports accurate positioning of the surface. Mechanical stops limit the travel, and electronic position and torque limiting protects both the actuator and the airframe structure. A film position transducer provides position feedback. A fail-safe brake is fitted on one variant only, so the variant must be chosen to match the required behavior on loss of power. The structural design is described as robust.

For integration, the actuator accepts an analog command input in the form of a DC voltage command signal and returns a position output signal. This analog interface suits servo loops that command surface position with a voltage and read back the achieved position. The unit runs from DC supply rails, and the applications engineers at the maker can adapt the design to the host system and its mission requirements.

No certifications or standards are listed for this actuator. Integrators who need qualification, environmental or electromagnetic data for a specific program should request it from the maker.

Typical applications are control surface actuation on target drones such as the AQM-37D and on other aerospace and defense uncrewed systems that need a compact rotary servo actuator with a defined stroke, speed and torque.